A reason for sending an interstellar mission to the white dwarf companions of Sirius and Procyon is that the white dwarfs are so dense, they might serve as sources of dark matter and/or energy. Maybe the dark energy they emit is too small to be noticed at this distance and by our present technology.

There might also be a nearby neutron star, just far enough away we haven't noticed its gravitational perturbations.

gladiolas wrote:What would be some plausible uses for dark matter and dark energy?

We don't even know what they are or how to detect them. How could we possibly come up with uses for them?

gladiolas wrote:A reason for sending an interstellar mission to the white dwarf companions of Sirius and Procyon is that the white dwarfs are so dense, they might serve as sources of dark matter and/or energy. Maybe the dark energy they emit is too small to be noticed at this distance and by our present technology.

I am very far removed from the cutting edge research on this, so I missed the announcement that dark matter and dark energy come from white dwarf stars (or at least might). What is the reason given that prompts this line of reasoning?

gladiolas wrote:There might also be a nearby neutron star, just far enough away we haven't noticed its gravitational perturbations.

No way to have dark matter life?

I/O error.

[Edit]Oh, I didn't notice that the is the Fictional Science forum. Sorry.

Ok. So you're proposing a sci-fi story where they've learned some things about Dark Matter and Dark Energy and decided that it somehow is a result of highly dense stars. Ok.

Well, at this point I would say that you could say whatever you want about those two things. Dark Matter Life? Sure. I could buy that. It doesn't appear to collect the same way regular matter does, so making structures might be hard. Evidently it doesn't even react with itself (according to my YouTube education).

Another thing to consider is that Dark Energy seems to be EVERYWHERE, which is why it is causing the universe to expand. If it was just around stars and other dense matter, then gravity and other forces could keep it in check, but it is not just around those things. It is in every little bit of space, and where there aren't sufficiently great wells of gravity to fight it, space itself gets stretched out.

So a use for Dark Energy might be, if you could somehow generate it on large scales, push another galaxy far away from your own. If you could somehow reverse it, negative Dark Energy, you could pull galaxies closer together.

Dark Matter, as I said (and I am most likely wrong because I am nobody special) doesn't appear to interact with anything, but it is influenced by gravity. So, you could maybe use it to play with gravity in some way. Maybe there is some energy field, like the Higgs Field, that you could invent that, when excited in some way, causes Dark Matter to interact, and therefore Dark Matter Life or something.

It is pretty wide open, since we know so little about these two things.

Like I said above, Gravity can nullify the expansion effects of Dark Energy by pulling matter together faster than Dark Energy pushes it apart. But there are other forces that work against Dark Energy, the forces that hold atoms together, the Strong force and the Electromagnetic force. If you can manipulate Dark Energy, however, and pump enough of it into a small enough area, you could rip apart atoms. Fire a Dark Energy beam at an opposing spaceship and BOOM! I wouldn't recommend doing it from up close, though. This could also be used to explain the Death Star as well.

Right now, we only have a few ideas of what Dark Matter could be. The prevailing hypothesis is that it is matter like neutrinos that doesn't interact electromagnetically, which is problematic for life as it means that small amounts can't clump together, only groups large enough to have enough gravitational force. Also, I don't know of a plausible mechanism for intelligence based on something other than electromagnetism.

Honesty replaced by greed, they gave us the reason to fight and bleedThey try to torch our faith and hope, spit at our presence and detest our goals

It's hard to imagine dark matter having much use beyond just being there and having gravity. And even if you did come up with a use for DM it's not easy to gather or store it due to its reticence to interact with itself or normal matter. You can't trap DM in a box made of normal matter since it doesn't interact with the matter comprising the walls of the box. The only way to trap it is gravitationally, but even that's not easy.

There is the possibility that DM feels the weak nuclear interaction (the WIMP hypothesis), although that's looking pretty unlikely these days, but even if it did it wouldn't help much in handling or harnessing DM, since the weak interaction is so weak except at very tiny distances.

A sufficiently large collection of normal matter collapses due to its self-gravity, but that doesn't work so well with DM. As matter (of any kind) collapses gravitationally it converts gravitational potential energy to kinetic energy. With normal matter that kinetic energy can be converted to heat via collisions, and the heat can radiate away; heat that doesn't get radiated outside the collapsing blob tends to make the blob expand (the heat is effectively converted back into kinetic energy), so it counteracts the gravitational collapse. With DM, the collisions don't happen (or have a miniscule probability of happening) so the DM particles have no way of losing their acquired kinetic energy, apart from turning it back into potential energy. So blobs of DM tend to be stable and resist collapsing.

PM 2Ring wrote:A sufficiently large collection of normal matter collapses due to its self-gravity, but that doesn't work so well with DM. As matter (of any kind) collapses gravitationally it converts gravitational potential energy to kinetic energy. With normal matter that kinetic energy can be converted to heat via collisions, and the heat can radiate away; heat that doesn't get radiated outside the collapsing blob tends to make the blob expand (the heat is effectively converted back into kinetic energy), so it counteracts the gravitational collapse. With DM, the collisions don't happen (or have a miniscule probability of happening) so the DM particles have no way of losing their acquired kinetic energy, apart from turning it back into potential energy. So blobs of DM tend to be stable and resist collapsing.

Hence the reason it exists in large, diffuse halos rather than hanging out in a disc.

You can trap dark matter particles if they happen to fall into a gravitational well without a high enough initial velocity to escape (which is really just a chance trick of orientation and angle). It will then oscillate back and forth within the well for a long time, hopefully until it is able to finally interact with something else via the weak nuclear interaction and annihilate. I like the idea of dark matter comprising WIMPs which are simply Planck-mass black holes, as this would seem to explain their behavior completely.

gladiolas wrote:What would be some plausible uses for dark matter and dark energy?

A reason for sending an interstellar mission to the white dwarf companions of Sirius and Procyon is that the white dwarfs are so dense, they might serve as sources of dark matter and/or energy. Maybe the dark energy they emit is too small to be noticed at this distance and by our present technology.

There might also be a nearby neutron star, just far enough away we haven't noticed its gravitational perturbations.

No way to have dark matter life?

Given that dark energy presumably causes the universe to expand, it's reasonable (from a sci-fi perspective) to assume it would be used for stuff like making wormholes and keeping them open.

gladiolas wrote:What would be some plausible uses for dark matter and dark energy?

A reason for sending an interstellar mission to the white dwarf companions of Sirius and Procyon is that the white dwarfs are so dense, they might serve as sources of dark matter and/or energy. Maybe the dark energy they emit is too small to be noticed at this distance and by our present technology.

There might also be a nearby neutron star, just far enough away we haven't noticed its gravitational perturbations.

No way to have dark matter life?

Given that dark energy presumably causes the universe to expand, it's reasonable (from a sci-fi perspective) to assume it would be used for stuff like making wormholes and keeping them open.

Exotic matter could *be* dark matter. Wikipedia has a list of possibilities.

Regarding Dark Energy--well, electromagnetism is a common way of transferring energy. Maybe one of the forms of Dark Energy is a fundamental force we don't know about, and Dark Matter could interact via one of those fundamental forces we don't know about...(and that could make Dark Matter life possible)....

sounds like I'm a bit desperate... I wanna write a sci-fi consistent with what we know...though I don't have a plot, setting or characters for it...

I know, we'd have to have the math to back up my idea about fundamental forces we don't know about.

Regarding Dark Energy--well, electromagnetism is a common way of transferring energy. Maybe one of the forms of Dark Energy is a fundamental force we don't know about, and Dark Matter could interact via one of those fundamental forces we don't know about...(and that could make Dark Matter life possible)....

Note that dark matter and dark energy probably have nothing to do with each other. They're both called "dark" just because we don't know much about them, and it's hard to find out more.

Dark matter probably doesn't interact at all with itself, or if it does, it does so very weakly. The dark matter halos we observe are consistent with particles that only interact gravitationally; if they interacted in any other way they'd probably clump more and produce an observably different shape.

I've only heard "exotic matter" used as a broad category, of which dark matter is an edge case of maybe-not-very-technically exotic matter because there's an awful lot of it and it seems to be quite ordinary in the universe. Like, a magnetic monopole would be exotic matter, and wouldn't need to be negative-mass to count.

So much depends upon a red wheel barrow (>= XXII) but it is not going to be installed.

There is a theory that dark matter is a WIMP (Weak Interacting Massive Particle). WIMPs only interact with matter with gravity and the weak interaction. The weak interaction and the electromagnetic interaction have been united, which is called the electroweak interaction. Put another way, they are the same thing expressed in different ways. That means that it should be, relatively, trivial to turn vector bosons* into photons.

What I would do, is make a space station that looks like a giant X. Because dark matter clumps form into halos (something that I did not know until reading this thread, so thanks) a structure can form a circle around the dark matter without touching it. The ends of the space station's arms are giant circles that surround the halo. I would then have the space station spin. This is for two reasons. First, spinning space stations generate artificial gravity, although the dark matter may do that for you. Second, it parallels how electricity is created from spinning magnets. Having a real-world parallel like that helps the reader suspend disbelief. The space station would be either a fueling station for passing space ships or a power plant that charges batteries and then sends them to other space stations or planets.

*Vector bosons are to the weak interaction as photons are to the electromagnetic interaction. This is, metaphorically, true in every possible way.